Preheat your oven to 400°F (200°C).
Dice the eggplant, zucchini, red bell pepper, and yellow onion into uniform half-inch pieces.
Heat the olive oil in a large oven-safe skillet over medium heat.
Add the onion and eggplant to the skillet, sautéing for 4-5 minutes until they begin to soften.
Stir in the zucchini, bell pepper, and minced garlic, cooking for another 3 minutes.
Pour in the tomato puree, dried oregano, sea salt, and black pepper, stirring to combine the vegetables into a thick sauce.
Season the chicken breast lightly with additional salt and pepper, then nestle it into the vegetable mixture in the skillet.
Transfer the skillet to the oven and bake for 18-22 minutes, or until the chicken reaches an internal temperature of 165°F.
Remove from the oven and let the dish rest for 5 minutes before garnishing with freshly chopped basil.